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<header> 91 <div class="header-container"> 92 <h1>Node.js v14.20.1 documentation</h1> 93 <button class="theme-toggle-btn" id="theme-toggle-btn" title="Toggle dark mode/light mode" aria-label="Toggle dark mode/light mode" hidden> 94 <svg xmlns="http://www.w3.org/2000/svg" class="icon dark-icon" height="24" width="24"> 95 <path fill="none" d="M0 0h24v24H0z" /> 96 <path d="M11.1 12.08c-2.33-4.51-.5-8.48.53-10.07C6.27 2.2 1.98 6.59 1.98 12c0 .14.02.28.02.42.62-.27 1.29-.42 2-.42 1.66 0 3.18.83 4.1 2.15A4.01 4.01 0 0111 18c0 1.52-.87 2.83-2.12 3.51.98.32 2.03.5 3.11.5 3.5 0 6.58-1.8 8.37-4.52-2.36.23-6.98-.97-9.26-5.41z"/> 97 <path d="M7 16h-.18C6.4 14.84 5.3 14 4 14c-1.66 0-3 1.34-3 3s1.34 3 3 3h3c1.1 0 2-.9 2-2s-.9-2-2-2z"/> 98 </svg> 99 <svg xmlns="http://www.w3.org/2000/svg" class="icon light-icon" height="24" width="24"> 100 <path d="M0 0h24v24H0z" fill="none" /> 101 <path d="M6.76 4.84l-1.8-1.79-1.41 1.41 1.79 1.79 1.42-1.41zM4 10.5H1v2h3v-2zm9-9.95h-2V3.5h2V.55zm7.45 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href="https://nodejs.org/docs/latest-v0.10.x/api/zlib.html">0.10.x</a></li></ol> 136 </li> 137 138 <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/master/doc/api/zlib.md">Edit on GitHub</a></li> 139 </ul> 140 </div> 141 <hr> 142 </header> 143 144 <details id="toc" open><summary>Table of contents</summary><ul> 145<li><span class="stability_2"><a href="#zlib_zlib">Zlib</a></span> 146<ul> 147<li><a href="#zlib_threadpool_usage_and_performance_considerations">Threadpool usage and performance considerations</a></li> 148<li><a href="#zlib_compressing_http_requests_and_responses">Compressing HTTP requests and responses</a></li> 149<li><a href="#zlib_memory_usage_tuning">Memory usage tuning</a> 150<ul> 151<li><a href="#zlib_for_zlib_based_streams">For zlib-based streams</a></li> 152<li><a href="#zlib_for_brotli_based_streams">For Brotli-based streams</a></li> 153</ul> 154</li> 155<li><a href="#zlib_flushing">Flushing</a></li> 156<li><a href="#zlib_constants">Constants</a> 157<ul> 158<li><a href="#zlib_zlib_constants">zlib constants</a></li> 159<li><a href="#zlib_brotli_constants">Brotli constants</a> 160<ul> 161<li><a href="#zlib_flush_operations">Flush operations</a></li> 162<li><a href="#zlib_compressor_options">Compressor options</a></li> 163<li><a href="#zlib_decompressor_options">Decompressor options</a></li> 164</ul> 165</li> 166</ul> 167</li> 168<li><a href="#zlib_class_options">Class: <code>Options</code></a></li> 169<li><a href="#zlib_class_brotlioptions">Class: <code>BrotliOptions</code></a></li> 170<li><a href="#zlib_class_zlib_brotlicompress">Class: <code>zlib.BrotliCompress</code></a></li> 171<li><a href="#zlib_class_zlib_brotlidecompress">Class: <code>zlib.BrotliDecompress</code></a></li> 172<li><a href="#zlib_class_zlib_deflate">Class: <code>zlib.Deflate</code></a></li> 173<li><a href="#zlib_class_zlib_deflateraw">Class: <code>zlib.DeflateRaw</code></a></li> 174<li><a href="#zlib_class_zlib_gunzip">Class: <code>zlib.Gunzip</code></a></li> 175<li><a href="#zlib_class_zlib_gzip">Class: <code>zlib.Gzip</code></a></li> 176<li><a href="#zlib_class_zlib_inflate">Class: <code>zlib.Inflate</code></a></li> 177<li><a href="#zlib_class_zlib_inflateraw">Class: <code>zlib.InflateRaw</code></a></li> 178<li><a href="#zlib_class_zlib_unzip">Class: <code>zlib.Unzip</code></a></li> 179<li><a href="#zlib_class_zlib_zlibbase">Class: <code>zlib.ZlibBase</code></a> 180<ul> 181<li><span class="stability_0"><a href="#zlib_zlib_bytesread"><code>zlib.bytesRead</code></a></span></li> 182<li><a href="#zlib_zlib_byteswritten"><code>zlib.bytesWritten</code></a></li> 183<li><a href="#zlib_zlib_close_callback"><code>zlib.close([callback])</code></a></li> 184<li><a href="#zlib_zlib_flush_kind_callback"><code>zlib.flush([kind, ]callback)</code></a></li> 185<li><a href="#zlib_zlib_params_level_strategy_callback"><code>zlib.params(level, strategy, callback)</code></a></li> 186<li><a href="#zlib_zlib_reset"><code>zlib.reset()</code></a></li> 187</ul> 188</li> 189<li><a href="#zlib_zlib_constants_1"><code>zlib.constants</code></a></li> 190<li><a href="#zlib_zlib_createbrotlicompress_options"><code>zlib.createBrotliCompress([options])</code></a></li> 191<li><a href="#zlib_zlib_createbrotlidecompress_options"><code>zlib.createBrotliDecompress([options])</code></a></li> 192<li><a href="#zlib_zlib_createdeflate_options"><code>zlib.createDeflate([options])</code></a></li> 193<li><a href="#zlib_zlib_createdeflateraw_options"><code>zlib.createDeflateRaw([options])</code></a></li> 194<li><a href="#zlib_zlib_creategunzip_options"><code>zlib.createGunzip([options])</code></a></li> 195<li><a href="#zlib_zlib_creategzip_options"><code>zlib.createGzip([options])</code></a></li> 196<li><a href="#zlib_zlib_createinflate_options"><code>zlib.createInflate([options])</code></a></li> 197<li><a href="#zlib_zlib_createinflateraw_options"><code>zlib.createInflateRaw([options])</code></a></li> 198<li><a href="#zlib_zlib_createunzip_options"><code>zlib.createUnzip([options])</code></a></li> 199<li><a href="#zlib_convenience_methods">Convenience methods</a> 200<ul> 201<li><a href="#zlib_zlib_brotlicompress_buffer_options_callback"><code>zlib.brotliCompress(buffer[, options], callback)</code></a></li> 202<li><a href="#zlib_zlib_brotlicompresssync_buffer_options"><code>zlib.brotliCompressSync(buffer[, options])</code></a></li> 203<li><a href="#zlib_zlib_brotlidecompress_buffer_options_callback"><code>zlib.brotliDecompress(buffer[, options], callback)</code></a></li> 204<li><a href="#zlib_zlib_brotlidecompresssync_buffer_options"><code>zlib.brotliDecompressSync(buffer[, options])</code></a></li> 205<li><a href="#zlib_zlib_deflate_buffer_options_callback"><code>zlib.deflate(buffer[, options], callback)</code></a></li> 206<li><a href="#zlib_zlib_deflatesync_buffer_options"><code>zlib.deflateSync(buffer[, options])</code></a></li> 207<li><a href="#zlib_zlib_deflateraw_buffer_options_callback"><code>zlib.deflateRaw(buffer[, options], callback)</code></a></li> 208<li><a href="#zlib_zlib_deflaterawsync_buffer_options"><code>zlib.deflateRawSync(buffer[, options])</code></a></li> 209<li><a href="#zlib_zlib_gunzip_buffer_options_callback"><code>zlib.gunzip(buffer[, options], callback)</code></a></li> 210<li><a href="#zlib_zlib_gunzipsync_buffer_options"><code>zlib.gunzipSync(buffer[, options])</code></a></li> 211<li><a href="#zlib_zlib_gzip_buffer_options_callback"><code>zlib.gzip(buffer[, options], callback)</code></a></li> 212<li><a href="#zlib_zlib_gzipsync_buffer_options"><code>zlib.gzipSync(buffer[, options])</code></a></li> 213<li><a href="#zlib_zlib_inflate_buffer_options_callback"><code>zlib.inflate(buffer[, options], callback)</code></a></li> 214<li><a href="#zlib_zlib_inflatesync_buffer_options"><code>zlib.inflateSync(buffer[, options])</code></a></li> 215<li><a href="#zlib_zlib_inflateraw_buffer_options_callback"><code>zlib.inflateRaw(buffer[, options], callback)</code></a></li> 216<li><a href="#zlib_zlib_inflaterawsync_buffer_options"><code>zlib.inflateRawSync(buffer[, options])</code></a></li> 217<li><a href="#zlib_zlib_unzip_buffer_options_callback"><code>zlib.unzip(buffer[, options], callback)</code></a></li> 218<li><a href="#zlib_zlib_unzipsync_buffer_options"><code>zlib.unzipSync(buffer[, options])</code></a></li> 219</ul> 220</li> 221</ul> 222</li> 223</ul></details> 224 225 <div id="apicontent"> 226 <h2>Zlib<span><a class="mark" href="#zlib_zlib" id="zlib_zlib">#</a></span></h2> 227 228<p></p><div class="api_stability api_stability_2"><a href="documentation.html#documentation_stability_index">Stability: 2</a> - Stable</div><p></p> 229<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v14.20.1/lib/zlib.js">lib/zlib.js</a></p> 230<p>The <code>zlib</code> module provides compression functionality implemented using Gzip, 231Deflate/Inflate, and Brotli.</p> 232<p>To access it:</p> 233<pre><code class="language-js"><span class="hljs-keyword">const</span> zlib = <span class="hljs-built_in">require</span>(<span class="hljs-string">'zlib'</span>);</code></pre> 234<p>Compression and decompression are built around the Node.js <a href="stream.html">Streams API</a>.</p> 235<p>Compressing or decompressing a stream (such as a file) can be accomplished by 236piping the source stream through a <code>zlib</code> <code>Transform</code> stream into a destination 237stream:</p> 238<pre><code class="language-js"><span class="hljs-keyword">const</span> { createGzip } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'zlib'</span>); 239<span class="hljs-keyword">const</span> { pipeline } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'stream'</span>); 240<span class="hljs-keyword">const</span> { 241 createReadStream, 242 createWriteStream 243} = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 244 245<span class="hljs-keyword">const</span> gzip = <span class="hljs-title function_">createGzip</span>(); 246<span class="hljs-keyword">const</span> source = <span class="hljs-title function_">createReadStream</span>(<span class="hljs-string">'input.txt'</span>); 247<span class="hljs-keyword">const</span> destination = <span class="hljs-title function_">createWriteStream</span>(<span class="hljs-string">'input.txt.gz'</span>); 248 249<span class="hljs-title function_">pipeline</span>(source, gzip, destination, <span class="hljs-function">(<span class="hljs-params">err</span>) =></span> { 250 <span class="hljs-keyword">if</span> (err) { 251 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'An error occurred:'</span>, err); 252 process.<span class="hljs-property">exitCode</span> = <span class="hljs-number">1</span>; 253 } 254}); 255 256<span class="hljs-comment">// Or, Promisified</span> 257 258<span class="hljs-keyword">const</span> { promisify } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'util'</span>); 259<span class="hljs-keyword">const</span> pipe = <span class="hljs-title function_">promisify</span>(pipeline); 260 261<span class="hljs-keyword">async</span> <span class="hljs-keyword">function</span> <span class="hljs-title function_">do_gzip</span>(<span class="hljs-params">input, output</span>) { 262 <span class="hljs-keyword">const</span> gzip = <span class="hljs-title function_">createGzip</span>(); 263 <span class="hljs-keyword">const</span> source = <span class="hljs-title function_">createReadStream</span>(input); 264 <span class="hljs-keyword">const</span> destination = <span class="hljs-title function_">createWriteStream</span>(output); 265 <span class="hljs-keyword">await</span> <span class="hljs-title function_">pipe</span>(source, gzip, destination); 266} 267 268<span class="hljs-title function_">do_gzip</span>(<span class="hljs-string">'input.txt'</span>, <span class="hljs-string">'input.txt.gz'</span>) 269 .<span class="hljs-title function_">catch</span>(<span class="hljs-function">(<span class="hljs-params">err</span>) =></span> { 270 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'An error occurred:'</span>, err); 271 process.<span class="hljs-property">exitCode</span> = <span class="hljs-number">1</span>; 272 });</code></pre> 273<p>It is also possible to compress or decompress data in a single step:</p> 274<pre><code class="language-js"><span class="hljs-keyword">const</span> { deflate, unzip } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'zlib'</span>); 275 276<span class="hljs-keyword">const</span> input = <span class="hljs-string">'.................................'</span>; 277<span class="hljs-title function_">deflate</span>(input, <span class="hljs-function">(<span class="hljs-params">err, buffer</span>) =></span> { 278 <span class="hljs-keyword">if</span> (err) { 279 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'An error occurred:'</span>, err); 280 process.<span class="hljs-property">exitCode</span> = <span class="hljs-number">1</span>; 281 } 282 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(buffer.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'base64'</span>)); 283}); 284 285<span class="hljs-keyword">const</span> buffer = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(<span class="hljs-string">'eJzT0yMAAGTvBe8='</span>, <span class="hljs-string">'base64'</span>); 286<span class="hljs-title function_">unzip</span>(buffer, <span class="hljs-function">(<span class="hljs-params">err, buffer</span>) =></span> { 287 <span class="hljs-keyword">if</span> (err) { 288 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'An error occurred:'</span>, err); 289 process.<span class="hljs-property">exitCode</span> = <span class="hljs-number">1</span>; 290 } 291 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(buffer.<span class="hljs-title function_">toString</span>()); 292}); 293 294<span class="hljs-comment">// Or, Promisified</span> 295 296<span class="hljs-keyword">const</span> { promisify } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'util'</span>); 297<span class="hljs-keyword">const</span> do_unzip = <span class="hljs-title function_">promisify</span>(unzip); 298 299<span class="hljs-title function_">do_unzip</span>(buffer) 300 .<span class="hljs-title function_">then</span>(<span class="hljs-function">(<span class="hljs-params">buf</span>) =></span> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(buf.<span class="hljs-title function_">toString</span>())) 301 .<span class="hljs-title function_">catch</span>(<span class="hljs-function">(<span class="hljs-params">err</span>) =></span> { 302 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'An error occurred:'</span>, err); 303 process.<span class="hljs-property">exitCode</span> = <span class="hljs-number">1</span>; 304 });</code></pre> 305<section><h3>Threadpool usage and performance considerations<span><a class="mark" href="#zlib_threadpool_usage_and_performance_considerations" id="zlib_threadpool_usage_and_performance_considerations">#</a></span></h3> 306<p>All <code>zlib</code> APIs, except those that are explicitly synchronous, use the Node.js 307internal threadpool. This can lead to surprising effects and performance 308limitations in some applications.</p> 309<p>Creating and using a large number of zlib objects simultaneously can cause 310significant memory fragmentation.</p> 311<pre><code class="language-js"><span class="hljs-keyword">const</span> zlib = <span class="hljs-built_in">require</span>(<span class="hljs-string">'zlib'</span>); 312 313<span class="hljs-keyword">const</span> payload = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(<span class="hljs-string">'This is some data'</span>); 314 315<span class="hljs-comment">// WARNING: DO NOT DO THIS!</span> 316<span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i < <span class="hljs-number">30000</span>; ++i) { 317 zlib.<span class="hljs-title function_">deflate</span>(payload, <span class="hljs-function">(<span class="hljs-params">err, buffer</span>) =></span> {}); 318}</code></pre> 319<p>In the preceding example, 30,000 deflate instances are created concurrently. 320Because of how some operating systems handle memory allocation and 321deallocation, this may lead to to significant memory fragmentation.</p> 322<p>It is strongly recommended that the results of compression 323operations be cached to avoid duplication of effort.</p> 324</section><section><h3>Compressing HTTP requests and responses<span><a class="mark" href="#zlib_compressing_http_requests_and_responses" id="zlib_compressing_http_requests_and_responses">#</a></span></h3> 325<p>The <code>zlib</code> module can be used to implement support for the <code>gzip</code>, <code>deflate</code> 326and <code>br</code> content-encoding mechanisms defined by 327<a href="https://tools.ietf.org/html/rfc7230#section-4.2">HTTP</a>.</p> 328<p>The HTTP <a href="https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3"><code>Accept-Encoding</code></a> header is used within an http request to identify 329the compression encodings accepted by the client. The <a href="https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.11"><code>Content-Encoding</code></a> 330header is used to identify the compression encodings actually applied to a 331message.</p> 332<p>The examples given below are drastically simplified to show the basic concept. 333Using <code>zlib</code> encoding can be expensive, and the results ought to be cached. 334See <a href="#zlib_memory_usage_tuning">Memory usage tuning</a> for more information on the speed/memory/compression 335tradeoffs involved in <code>zlib</code> usage.</p> 336<pre><code class="language-js"><span class="hljs-comment">// Client request example</span> 337<span class="hljs-keyword">const</span> zlib = <span class="hljs-built_in">require</span>(<span class="hljs-string">'zlib'</span>); 338<span class="hljs-keyword">const</span> http = <span class="hljs-built_in">require</span>(<span class="hljs-string">'http'</span>); 339<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 340<span class="hljs-keyword">const</span> { pipeline } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'stream'</span>); 341 342<span class="hljs-keyword">const</span> request = http.<span class="hljs-title function_">get</span>({ <span class="hljs-attr">host</span>: <span class="hljs-string">'example.com'</span>, 343 <span class="hljs-attr">path</span>: <span class="hljs-string">'/'</span>, 344 <span class="hljs-attr">port</span>: <span class="hljs-number">80</span>, 345 <span class="hljs-attr">headers</span>: { <span class="hljs-string">'Accept-Encoding'</span>: <span class="hljs-string">'br,gzip,deflate'</span> } }); 346request.<span class="hljs-title function_">on</span>(<span class="hljs-string">'response'</span>, <span class="hljs-function">(<span class="hljs-params">response</span>) =></span> { 347 <span class="hljs-keyword">const</span> output = fs.<span class="hljs-title function_">createWriteStream</span>(<span class="hljs-string">'example.com_index.html'</span>); 348 349 <span class="hljs-keyword">const</span> <span class="hljs-title function_">onError</span> = (<span class="hljs-params">err</span>) => { 350 <span class="hljs-keyword">if</span> (err) { 351 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'An error occurred:'</span>, err); 352 process.<span class="hljs-property">exitCode</span> = <span class="hljs-number">1</span>; 353 } 354 }; 355 356 <span class="hljs-keyword">switch</span> (response.<span class="hljs-property">headers</span>[<span class="hljs-string">'content-encoding'</span>]) { 357 <span class="hljs-keyword">case</span> <span class="hljs-string">'br'</span>: 358 <span class="hljs-title function_">pipeline</span>(response, zlib.<span class="hljs-title function_">createBrotliDecompress</span>(), output, onError); 359 <span class="hljs-keyword">break</span>; 360 <span class="hljs-comment">// Or, just use zlib.createUnzip() to handle both of the following cases:</span> 361 <span class="hljs-keyword">case</span> <span class="hljs-string">'gzip'</span>: 362 <span class="hljs-title function_">pipeline</span>(response, zlib.<span class="hljs-title function_">createGunzip</span>(), output, onError); 363 <span class="hljs-keyword">break</span>; 364 <span class="hljs-keyword">case</span> <span class="hljs-string">'deflate'</span>: 365 <span class="hljs-title function_">pipeline</span>(response, zlib.<span class="hljs-title function_">createInflate</span>(), output, onError); 366 <span class="hljs-keyword">break</span>; 367 <span class="hljs-attr">default</span>: 368 <span class="hljs-title function_">pipeline</span>(response, output, onError); 369 <span class="hljs-keyword">break</span>; 370 } 371});</code></pre> 372<pre><code class="language-js"><span class="hljs-comment">// server example</span> 373<span class="hljs-comment">// Running a gzip operation on every request is quite expensive.</span> 374<span class="hljs-comment">// It would be much more efficient to cache the compressed buffer.</span> 375<span class="hljs-keyword">const</span> zlib = <span class="hljs-built_in">require</span>(<span class="hljs-string">'zlib'</span>); 376<span class="hljs-keyword">const</span> http = <span class="hljs-built_in">require</span>(<span class="hljs-string">'http'</span>); 377<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 378<span class="hljs-keyword">const</span> { pipeline } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'stream'</span>); 379 380http.<span class="hljs-title function_">createServer</span>(<span class="hljs-function">(<span class="hljs-params">request, response</span>) =></span> { 381 <span class="hljs-keyword">const</span> raw = fs.<span class="hljs-title function_">createReadStream</span>(<span class="hljs-string">'index.html'</span>); 382 <span class="hljs-comment">// Store both a compressed and an uncompressed version of the resource.</span> 383 response.<span class="hljs-title function_">setHeader</span>(<span class="hljs-string">'Vary'</span>, <span class="hljs-string">'Accept-Encoding'</span>); 384 <span class="hljs-keyword">let</span> acceptEncoding = request.<span class="hljs-property">headers</span>[<span class="hljs-string">'accept-encoding'</span>]; 385 <span class="hljs-keyword">if</span> (!acceptEncoding) { 386 acceptEncoding = <span class="hljs-string">''</span>; 387 } 388 389 <span class="hljs-keyword">const</span> <span class="hljs-title function_">onError</span> = (<span class="hljs-params">err</span>) => { 390 <span class="hljs-keyword">if</span> (err) { 391 <span class="hljs-comment">// If an error occurs, there's not much we can do because</span> 392 <span class="hljs-comment">// the server has already sent the 200 response code and</span> 393 <span class="hljs-comment">// some amount of data has already been sent to the client.</span> 394 <span class="hljs-comment">// The best we can do is terminate the response immediately</span> 395 <span class="hljs-comment">// and log the error.</span> 396 response.<span class="hljs-title function_">end</span>(); 397 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'An error occurred:'</span>, err); 398 } 399 }; 400 401 <span class="hljs-comment">// Note: This is not a conformant accept-encoding parser.</span> 402 <span class="hljs-comment">// See https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3</span> 403 <span class="hljs-keyword">if</span> (<span class="hljs-regexp">/\bdeflate\b/</span>.<span class="hljs-title function_">test</span>(acceptEncoding)) { 404 response.<span class="hljs-title function_">writeHead</span>(<span class="hljs-number">200</span>, { <span class="hljs-string">'Content-Encoding'</span>: <span class="hljs-string">'deflate'</span> }); 405 <span class="hljs-title function_">pipeline</span>(raw, zlib.<span class="hljs-title function_">createDeflate</span>(), response, onError); 406 } <span class="hljs-keyword">else</span> <span class="hljs-keyword">if</span> (<span class="hljs-regexp">/\bgzip\b/</span>.<span class="hljs-title function_">test</span>(acceptEncoding)) { 407 response.<span class="hljs-title function_">writeHead</span>(<span class="hljs-number">200</span>, { <span class="hljs-string">'Content-Encoding'</span>: <span class="hljs-string">'gzip'</span> }); 408 <span class="hljs-title function_">pipeline</span>(raw, zlib.<span class="hljs-title function_">createGzip</span>(), response, onError); 409 } <span class="hljs-keyword">else</span> <span class="hljs-keyword">if</span> (<span class="hljs-regexp">/\bbr\b/</span>.<span class="hljs-title function_">test</span>(acceptEncoding)) { 410 response.<span class="hljs-title function_">writeHead</span>(<span class="hljs-number">200</span>, { <span class="hljs-string">'Content-Encoding'</span>: <span class="hljs-string">'br'</span> }); 411 <span class="hljs-title function_">pipeline</span>(raw, zlib.<span class="hljs-title function_">createBrotliCompress</span>(), response, onError); 412 } <span class="hljs-keyword">else</span> { 413 response.<span class="hljs-title function_">writeHead</span>(<span class="hljs-number">200</span>, {}); 414 <span class="hljs-title function_">pipeline</span>(raw, response, onError); 415 } 416}).<span class="hljs-title function_">listen</span>(<span class="hljs-number">1337</span>);</code></pre> 417<p>By default, the <code>zlib</code> methods will throw an error when decompressing 418truncated data. However, if it is known that the data is incomplete, or 419the desire is to inspect only the beginning of a compressed file, it is 420possible to suppress the default error handling by changing the flushing 421method that is used to decompress the last chunk of input data:</p> 422<pre><code class="language-js"><span class="hljs-comment">// This is a truncated version of the buffer from the above examples</span> 423<span class="hljs-keyword">const</span> buffer = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(<span class="hljs-string">'eJzT0yMA'</span>, <span class="hljs-string">'base64'</span>); 424 425zlib.<span class="hljs-title function_">unzip</span>( 426 buffer, 427 <span class="hljs-comment">// For Brotli, the equivalent is zlib.constants.BROTLI_OPERATION_FLUSH.</span> 428 { <span class="hljs-attr">finishFlush</span>: zlib.<span class="hljs-property">constants</span>.<span class="hljs-property">Z_SYNC_FLUSH</span> }, 429 <span class="hljs-function">(<span class="hljs-params">err, buffer</span>) =></span> { 430 <span class="hljs-keyword">if</span> (err) { 431 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'An error occurred:'</span>, err); 432 process.<span class="hljs-property">exitCode</span> = <span class="hljs-number">1</span>; 433 } 434 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(buffer.<span class="hljs-title function_">toString</span>()); 435 });</code></pre> 436<p>This will not change the behavior in other error-throwing situations, e.g. 437when the input data has an invalid format. Using this method, it will not be 438possible to determine whether the input ended prematurely or lacks the 439integrity checks, making it necessary to manually check that the 440decompressed result is valid.</p> 441</section><section><h3>Memory usage tuning<span><a class="mark" href="#zlib_memory_usage_tuning" id="zlib_memory_usage_tuning">#</a></span></h3> 442 443<h4>For zlib-based streams<span><a class="mark" href="#zlib_for_zlib_based_streams" id="zlib_for_zlib_based_streams">#</a></span></h4> 444<p>From <code>zlib/zconf.h</code>, modified for Node.js usage:</p> 445<p>The memory requirements for deflate are (in bytes):</p> 446<!-- eslint-disable semi --> 447<pre><code class="language-js">(<span class="hljs-number">1</span> << (windowBits + <span class="hljs-number">2</span>)) + (<span class="hljs-number">1</span> << (memLevel + <span class="hljs-number">9</span>))</code></pre> 448<p>That is: 128K for <code>windowBits</code> = 15 + 128K for <code>memLevel</code> = 8 449(default values) plus a few kilobytes for small objects.</p> 450<p>For example, to reduce the default memory requirements from 256K to 128K, the 451options should be set to:</p> 452<pre><code class="language-js"><span class="hljs-keyword">const</span> options = { <span class="hljs-attr">windowBits</span>: <span class="hljs-number">14</span>, <span class="hljs-attr">memLevel</span>: <span class="hljs-number">7</span> };</code></pre> 453<p>This will, however, generally degrade compression.</p> 454<p>The memory requirements for inflate are (in bytes) <code>1 << windowBits</code>. 455That is, 32K for <code>windowBits</code> = 15 (default value) plus a few kilobytes 456for small objects.</p> 457<p>This is in addition to a single internal output slab buffer of size 458<code>chunkSize</code>, which defaults to 16K.</p> 459<p>The speed of <code>zlib</code> compression is affected most dramatically by the 460<code>level</code> setting. A higher level will result in better compression, but 461will take longer to complete. A lower level will result in less 462compression, but will be much faster.</p> 463<p>In general, greater memory usage options will mean that Node.js has to make 464fewer calls to <code>zlib</code> because it will be able to process more data on 465each <code>write</code> operation. So, this is another factor that affects the 466speed, at the cost of memory usage.</p> 467<h4>For Brotli-based streams<span><a class="mark" href="#zlib_for_brotli_based_streams" id="zlib_for_brotli_based_streams">#</a></span></h4> 468<p>There are equivalents to the zlib options for Brotli-based streams, although 469these options have different ranges than the zlib ones:</p> 470<ul> 471<li>zlib’s <code>level</code> option matches Brotli’s <code>BROTLI_PARAM_QUALITY</code> option.</li> 472<li>zlib’s <code>windowBits</code> option matches Brotli’s <code>BROTLI_PARAM_LGWIN</code> option.</li> 473</ul> 474<p>See <a href="#zlib_brotli_constants">below</a> for more details on Brotli-specific options.</p> 475</section><section><h3>Flushing<span><a class="mark" href="#zlib_flushing" id="zlib_flushing">#</a></span></h3> 476<p>Calling <a href="#zlib_zlib_flush_kind_callback"><code>.flush()</code></a> on a compression stream will make <code>zlib</code> return as much 477output as currently possible. This may come at the cost of degraded compression 478quality, but can be useful when data needs to be available as soon as possible.</p> 479<p>In the following example, <code>flush()</code> is used to write a compressed partial 480HTTP response to the client:</p> 481<pre><code class="language-js"><span class="hljs-keyword">const</span> zlib = <span class="hljs-built_in">require</span>(<span class="hljs-string">'zlib'</span>); 482<span class="hljs-keyword">const</span> http = <span class="hljs-built_in">require</span>(<span class="hljs-string">'http'</span>); 483<span class="hljs-keyword">const</span> { pipeline } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'stream'</span>); 484 485http.<span class="hljs-title function_">createServer</span>(<span class="hljs-function">(<span class="hljs-params">request, response</span>) =></span> { 486 <span class="hljs-comment">// For the sake of simplicity, the Accept-Encoding checks are omitted.</span> 487 response.<span class="hljs-title function_">writeHead</span>(<span class="hljs-number">200</span>, { <span class="hljs-string">'content-encoding'</span>: <span class="hljs-string">'gzip'</span> }); 488 <span class="hljs-keyword">const</span> output = zlib.<span class="hljs-title function_">createGzip</span>(); 489 <span class="hljs-keyword">let</span> i; 490 491 <span class="hljs-title function_">pipeline</span>(output, response, <span class="hljs-function">(<span class="hljs-params">err</span>) =></span> { 492 <span class="hljs-keyword">if</span> (err) { 493 <span class="hljs-comment">// If an error occurs, there's not much we can do because</span> 494 <span class="hljs-comment">// the server has already sent the 200 response code and</span> 495 <span class="hljs-comment">// some amount of data has already been sent to the client.</span> 496 <span class="hljs-comment">// The best we can do is terminate the response immediately</span> 497 <span class="hljs-comment">// and log the error.</span> 498 <span class="hljs-built_in">clearInterval</span>(i); 499 response.<span class="hljs-title function_">end</span>(); 500 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'An error occurred:'</span>, err); 501 } 502 }); 503 504 i = <span class="hljs-built_in">setInterval</span>(<span class="hljs-function">() =></span> { 505 output.<span class="hljs-title function_">write</span>(<span class="hljs-string">`The current time is <span class="hljs-subst">${<span class="hljs-built_in">Date</span>()}</span>\n`</span>, <span class="hljs-function">() =></span> { 506 <span class="hljs-comment">// The data has been passed to zlib, but the compression algorithm may</span> 507 <span class="hljs-comment">// have decided to buffer the data for more efficient compression.</span> 508 <span class="hljs-comment">// Calling .flush() will make the data available as soon as the client</span> 509 <span class="hljs-comment">// is ready to receive it.</span> 510 output.<span class="hljs-title function_">flush</span>(); 511 }); 512 }, <span class="hljs-number">1000</span>); 513}).<span class="hljs-title function_">listen</span>(<span class="hljs-number">1337</span>);</code></pre> 514</section><section><h3>Constants<span><a class="mark" href="#zlib_constants" id="zlib_constants">#</a></span></h3> 515<div class="api_metadata"> 516<span>Added in: v0.5.8</span> 517</div> 518 519<h4>zlib constants<span><a class="mark" href="#zlib_zlib_constants" id="zlib_zlib_constants">#</a></span></h4> 520<p>All of the constants defined in <code>zlib.h</code> are also defined on 521<code>require('zlib').constants</code>. In the normal course of operations, it will not be 522necessary to use these constants. They are documented so that their presence is 523not surprising. This section is taken almost directly from the 524<a href="https://zlib.net/manual.html#Constants">zlib documentation</a>.</p> 525<p>Previously, the constants were available directly from <code>require('zlib')</code>, for 526instance <code>zlib.Z_NO_FLUSH</code>. Accessing the constants directly from the module is 527currently still possible but is deprecated.</p> 528<p>Allowed flush values.</p> 529<ul> 530<li><code>zlib.constants.Z_NO_FLUSH</code></li> 531<li><code>zlib.constants.Z_PARTIAL_FLUSH</code></li> 532<li><code>zlib.constants.Z_SYNC_FLUSH</code></li> 533<li><code>zlib.constants.Z_FULL_FLUSH</code></li> 534<li><code>zlib.constants.Z_FINISH</code></li> 535<li><code>zlib.constants.Z_BLOCK</code></li> 536<li><code>zlib.constants.Z_TREES</code></li> 537</ul> 538<p>Return codes for the compression/decompression functions. Negative 539values are errors, positive values are used for special but normal 540events.</p> 541<ul> 542<li><code>zlib.constants.Z_OK</code></li> 543<li><code>zlib.constants.Z_STREAM_END</code></li> 544<li><code>zlib.constants.Z_NEED_DICT</code></li> 545<li><code>zlib.constants.Z_ERRNO</code></li> 546<li><code>zlib.constants.Z_STREAM_ERROR</code></li> 547<li><code>zlib.constants.Z_DATA_ERROR</code></li> 548<li><code>zlib.constants.Z_MEM_ERROR</code></li> 549<li><code>zlib.constants.Z_BUF_ERROR</code></li> 550<li><code>zlib.constants.Z_VERSION_ERROR</code></li> 551</ul> 552<p>Compression levels.</p> 553<ul> 554<li><code>zlib.constants.Z_NO_COMPRESSION</code></li> 555<li><code>zlib.constants.Z_BEST_SPEED</code></li> 556<li><code>zlib.constants.Z_BEST_COMPRESSION</code></li> 557<li><code>zlib.constants.Z_DEFAULT_COMPRESSION</code></li> 558</ul> 559<p>Compression strategy.</p> 560<ul> 561<li><code>zlib.constants.Z_FILTERED</code></li> 562<li><code>zlib.constants.Z_HUFFMAN_ONLY</code></li> 563<li><code>zlib.constants.Z_RLE</code></li> 564<li><code>zlib.constants.Z_FIXED</code></li> 565<li><code>zlib.constants.Z_DEFAULT_STRATEGY</code></li> 566</ul> 567<h4>Brotli constants<span><a class="mark" href="#zlib_brotli_constants" id="zlib_brotli_constants">#</a></span></h4> 568<div class="api_metadata"> 569<span>Added in: v11.7.0, v10.16.0</span> 570</div> 571<p>There are several options and other constants available for Brotli-based 572streams:</p> 573<h5>Flush operations<span><a class="mark" href="#zlib_flush_operations" id="zlib_flush_operations">#</a></span></h5> 574<p>The following values are valid flush operations for Brotli-based streams:</p> 575<ul> 576<li><code>zlib.constants.BROTLI_OPERATION_PROCESS</code> (default for all operations)</li> 577<li><code>zlib.constants.BROTLI_OPERATION_FLUSH</code> (default when calling <code>.flush()</code>)</li> 578<li><code>zlib.constants.BROTLI_OPERATION_FINISH</code> (default for the last chunk)</li> 579<li><code>zlib.constants.BROTLI_OPERATION_EMIT_METADATA</code> 580<ul> 581<li>This particular operation may be hard to use in a Node.js context, 582as the streaming layer makes it hard to know which data will end up 583in this frame. Also, there is currently no way to consume this data through 584the Node.js API.</li> 585</ul> 586</li> 587</ul> 588<h5>Compressor options<span><a class="mark" href="#zlib_compressor_options" id="zlib_compressor_options">#</a></span></h5> 589<p>There are several options that can be set on Brotli encoders, affecting 590compression efficiency and speed. Both the keys and the values can be accessed 591as properties of the <code>zlib.constants</code> object.</p> 592<p>The most important options are:</p> 593<ul> 594<li><code>BROTLI_PARAM_MODE</code> 595<ul> 596<li><code>BROTLI_MODE_GENERIC</code> (default)</li> 597<li><code>BROTLI_MODE_TEXT</code>, adjusted for UTF-8 text</li> 598<li><code>BROTLI_MODE_FONT</code>, adjusted for WOFF 2.0 fonts</li> 599</ul> 600</li> 601<li><code>BROTLI_PARAM_QUALITY</code> 602<ul> 603<li>Ranges from <code>BROTLI_MIN_QUALITY</code> to <code>BROTLI_MAX_QUALITY</code>, 604with a default of <code>BROTLI_DEFAULT_QUALITY</code>.</li> 605</ul> 606</li> 607<li><code>BROTLI_PARAM_SIZE_HINT</code> 608<ul> 609<li>Integer value representing the expected input size; 610defaults to <code>0</code> for an unknown input size.</li> 611</ul> 612</li> 613</ul> 614<p>The following flags can be set for advanced control over the compression 615algorithm and memory usage tuning:</p> 616<ul> 617<li><code>BROTLI_PARAM_LGWIN</code> 618<ul> 619<li>Ranges from <code>BROTLI_MIN_WINDOW_BITS</code> to <code>BROTLI_MAX_WINDOW_BITS</code>, 620with a default of <code>BROTLI_DEFAULT_WINDOW</code>, or up to 621<code>BROTLI_LARGE_MAX_WINDOW_BITS</code> if the <code>BROTLI_PARAM_LARGE_WINDOW</code> flag 622is set.</li> 623</ul> 624</li> 625<li><code>BROTLI_PARAM_LGBLOCK</code> 626<ul> 627<li>Ranges from <code>BROTLI_MIN_INPUT_BLOCK_BITS</code> to <code>BROTLI_MAX_INPUT_BLOCK_BITS</code>.</li> 628</ul> 629</li> 630<li><code>BROTLI_PARAM_DISABLE_LITERAL_CONTEXT_MODELING</code> 631<ul> 632<li>Boolean flag that decreases compression ratio in favour of 633decompression speed.</li> 634</ul> 635</li> 636<li><code>BROTLI_PARAM_LARGE_WINDOW</code> 637<ul> 638<li>Boolean flag enabling “Large Window Brotli” mode (not compatible with the 639Brotli format as standardized in <a href="https://www.rfc-editor.org/rfc/rfc7932.txt">RFC 7932</a>).</li> 640</ul> 641</li> 642<li><code>BROTLI_PARAM_NPOSTFIX</code> 643<ul> 644<li>Ranges from <code>0</code> to <code>BROTLI_MAX_NPOSTFIX</code>.</li> 645</ul> 646</li> 647<li><code>BROTLI_PARAM_NDIRECT</code> 648<ul> 649<li>Ranges from <code>0</code> to <code>15 << NPOSTFIX</code> in steps of <code>1 << NPOSTFIX</code>.</li> 650</ul> 651</li> 652</ul> 653<h5>Decompressor options<span><a class="mark" href="#zlib_decompressor_options" id="zlib_decompressor_options">#</a></span></h5> 654<p>These advanced options are available for controlling decompression:</p> 655<ul> 656<li><code>BROTLI_DECODER_PARAM_DISABLE_RING_BUFFER_REALLOCATION</code> 657<ul> 658<li>Boolean flag that affects internal memory allocation patterns.</li> 659</ul> 660</li> 661<li><code>BROTLI_DECODER_PARAM_LARGE_WINDOW</code> 662<ul> 663<li>Boolean flag enabling “Large Window Brotli” mode (not compatible with the 664Brotli format as standardized in <a href="https://www.rfc-editor.org/rfc/rfc7932.txt">RFC 7932</a>).</li> 665</ul> 666</li> 667</ul> 668</section><section><h3>Class: <code>Options</code><span><a class="mark" href="#zlib_class_options" id="zlib_class_options">#</a></span></h3> 669<div class="api_metadata"> 670<details class="changelog"><summary>History</summary> 671<table> 672<tbody><tr><th>Version</th><th>Changes</th></tr> 673<tr><td>v14.5.0, v12.19.0</td> 674<td><p>The <code>maxOutputLength</code> option is supported now.</p></td></tr> 675<tr><td>v9.4.0</td> 676<td><p>The <code>dictionary</code> option can be an <code>ArrayBuffer</code>.</p></td></tr> 677<tr><td>v8.0.0</td> 678<td><p>The <code>dictionary</code> option can be an <code>Uint8Array</code> now.</p></td></tr> 679<tr><td>v5.11.0</td> 680<td><p>The <code>finishFlush</code> option is supported now.</p></td></tr> 681<tr><td>v0.11.1</td> 682<td><p><span>Added in: v0.11.1</span></p></td></tr> 683</tbody></table> 684</details> 685</div> 686 687<p>Each zlib-based class takes an <code>options</code> object. No options are required.</p> 688<p>Some options are only relevant when compressing and are 689ignored by the decompression classes.</p> 690<ul> 691<li><code>flush</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> <strong>Default:</strong> <code>zlib.constants.Z_NO_FLUSH</code></li> 692<li><code>finishFlush</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> <strong>Default:</strong> <code>zlib.constants.Z_FINISH</code></li> 693<li><code>chunkSize</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> <strong>Default:</strong> <code>16 * 1024</code></li> 694<li><code>windowBits</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a></li> 695<li><code>level</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> (compression only)</li> 696<li><code>memLevel</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> (compression only)</li> 697<li><code>strategy</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> (compression only)</li> 698<li><code>dictionary</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> (deflate/inflate only, 699empty dictionary by default)</li> 700<li><code>info</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> (If <code>true</code>, returns an object with <code>buffer</code> and <code>engine</code>.)</li> 701<li><code>maxOutputLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Limits output size when using 702<a href="#zlib_convenience_methods">convenience methods</a>. <strong>Default:</strong> <a href="buffer.html#buffer_buffer_kmaxlength"><code>buffer.kMaxLength</code></a></li> 703</ul> 704<p>See the <a href="https://zlib.net/manual.html#Advanced"><code>deflateInit2</code> and <code>inflateInit2</code></a> documentation for more 705information.</p> 706</section><section><h3>Class: <code>BrotliOptions</code><span><a class="mark" href="#zlib_class_brotlioptions" id="zlib_class_brotlioptions">#</a></span></h3> 707<div class="api_metadata"> 708<details class="changelog"><summary>History</summary> 709<table> 710<tbody><tr><th>Version</th><th>Changes</th></tr> 711<tr><td>v14.5.0</td> 712<td><p>The <code>maxOutputLength</code> option is supported now.</p></td></tr> 713<tr><td>v11.7.0</td> 714<td><p><span>Added in: v11.7.0</span></p></td></tr> 715</tbody></table> 716</details> 717</div> 718 719<p>Each Brotli-based class takes an <code>options</code> object. All options are optional.</p> 720<ul> 721<li><code>flush</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> <strong>Default:</strong> <code>zlib.constants.BROTLI_OPERATION_PROCESS</code></li> 722<li><code>finishFlush</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> <strong>Default:</strong> <code>zlib.constants.BROTLI_OPERATION_FINISH</code></li> 723<li><code>chunkSize</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> <strong>Default:</strong> <code>16 * 1024</code></li> 724<li><code>params</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> Key-value object containing indexed <a href="#zlib_brotli_constants">Brotli parameters</a>.</li> 725<li><code>maxOutputLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Limits output size when using 726<a href="#zlib_convenience_methods">convenience methods</a>. <strong>Default:</strong> <a href="buffer.html#buffer_buffer_kmaxlength"><code>buffer.kMaxLength</code></a></li> 727</ul> 728<p>For example:</p> 729<pre><code class="language-js"><span class="hljs-keyword">const</span> stream = zlib.<span class="hljs-title function_">createBrotliCompress</span>({ 730 <span class="hljs-attr">chunkSize</span>: <span class="hljs-number">32</span> * <span class="hljs-number">1024</span>, 731 <span class="hljs-attr">params</span>: { 732 [zlib.<span class="hljs-property">constants</span>.<span class="hljs-property">BROTLI_PARAM_MODE</span>]: zlib.<span class="hljs-property">constants</span>.<span class="hljs-property">BROTLI_MODE_TEXT</span>, 733 [zlib.<span class="hljs-property">constants</span>.<span class="hljs-property">BROTLI_PARAM_QUALITY</span>]: <span class="hljs-number">4</span>, 734 [zlib.<span class="hljs-property">constants</span>.<span class="hljs-property">BROTLI_PARAM_SIZE_HINT</span>]: fs.<span class="hljs-title function_">statSync</span>(inputFile).<span class="hljs-property">size</span> 735 } 736});</code></pre> 737</section><section><h3>Class: <code>zlib.BrotliCompress</code><span><a class="mark" href="#zlib_class_zlib_brotlicompress" id="zlib_class_zlib_brotlicompress">#</a></span></h3> 738<div class="api_metadata"> 739<span>Added in: v11.7.0, v10.16.0</span> 740</div> 741<p>Compress data using the Brotli algorithm.</p> 742</section><section><h3>Class: <code>zlib.BrotliDecompress</code><span><a class="mark" href="#zlib_class_zlib_brotlidecompress" id="zlib_class_zlib_brotlidecompress">#</a></span></h3> 743<div class="api_metadata"> 744<span>Added in: v11.7.0, v10.16.0</span> 745</div> 746<p>Decompress data using the Brotli algorithm.</p> 747</section><section><h3>Class: <code>zlib.Deflate</code><span><a class="mark" href="#zlib_class_zlib_deflate" id="zlib_class_zlib_deflate">#</a></span></h3> 748<div class="api_metadata"> 749<span>Added in: v0.5.8</span> 750</div> 751<p>Compress data using deflate.</p> 752</section><section><h3>Class: <code>zlib.DeflateRaw</code><span><a class="mark" href="#zlib_class_zlib_deflateraw" id="zlib_class_zlib_deflateraw">#</a></span></h3> 753<div class="api_metadata"> 754<span>Added in: v0.5.8</span> 755</div> 756<p>Compress data using deflate, and do not append a <code>zlib</code> header.</p> 757</section><section><h3>Class: <code>zlib.Gunzip</code><span><a class="mark" href="#zlib_class_zlib_gunzip" id="zlib_class_zlib_gunzip">#</a></span></h3> 758<div class="api_metadata"> 759<details class="changelog"><summary>History</summary> 760<table> 761<tbody><tr><th>Version</th><th>Changes</th></tr> 762<tr><td>v6.0.0</td> 763<td><p>Trailing garbage at the end of the input stream will now result in an <code>'error'</code> event.</p></td></tr> 764<tr><td>v5.9.0</td> 765<td><p>Multiple concatenated gzip file members are supported now.</p></td></tr> 766<tr><td>v5.0.0</td> 767<td><p>A truncated input stream will now result in an <code>'error'</code> event.</p></td></tr> 768<tr><td>v0.5.8</td> 769<td><p><span>Added in: v0.5.8</span></p></td></tr> 770</tbody></table> 771</details> 772</div> 773<p>Decompress a gzip stream.</p> 774</section><section><h3>Class: <code>zlib.Gzip</code><span><a class="mark" href="#zlib_class_zlib_gzip" id="zlib_class_zlib_gzip">#</a></span></h3> 775<div class="api_metadata"> 776<span>Added in: v0.5.8</span> 777</div> 778<p>Compress data using gzip.</p> 779</section><section><h3>Class: <code>zlib.Inflate</code><span><a class="mark" href="#zlib_class_zlib_inflate" id="zlib_class_zlib_inflate">#</a></span></h3> 780<div class="api_metadata"> 781<details class="changelog"><summary>History</summary> 782<table> 783<tbody><tr><th>Version</th><th>Changes</th></tr> 784<tr><td>v5.0.0</td> 785<td><p>A truncated input stream will now result in an <code>'error'</code> event.</p></td></tr> 786<tr><td>v0.5.8</td> 787<td><p><span>Added in: v0.5.8</span></p></td></tr> 788</tbody></table> 789</details> 790</div> 791<p>Decompress a deflate stream.</p> 792</section><section><h3>Class: <code>zlib.InflateRaw</code><span><a class="mark" href="#zlib_class_zlib_inflateraw" id="zlib_class_zlib_inflateraw">#</a></span></h3> 793<div class="api_metadata"> 794<details class="changelog"><summary>History</summary> 795<table> 796<tbody><tr><th>Version</th><th>Changes</th></tr> 797<tr><td>v6.8.0</td> 798<td><p>Custom dictionaries are now supported by <code>InflateRaw</code>.</p></td></tr> 799<tr><td>v5.0.0</td> 800<td><p>A truncated input stream will now result in an <code>'error'</code> event.</p></td></tr> 801<tr><td>v0.5.8</td> 802<td><p><span>Added in: v0.5.8</span></p></td></tr> 803</tbody></table> 804</details> 805</div> 806<p>Decompress a raw deflate stream.</p> 807</section><section><h3>Class: <code>zlib.Unzip</code><span><a class="mark" href="#zlib_class_zlib_unzip" id="zlib_class_zlib_unzip">#</a></span></h3> 808<div class="api_metadata"> 809<span>Added in: v0.5.8</span> 810</div> 811<p>Decompress either a Gzip- or Deflate-compressed stream by auto-detecting 812the header.</p> 813</section><section><h3>Class: <code>zlib.ZlibBase</code><span><a class="mark" href="#zlib_class_zlib_zlibbase" id="zlib_class_zlib_zlibbase">#</a></span></h3> 814<div class="api_metadata"> 815<details class="changelog"><summary>History</summary> 816<table> 817<tbody><tr><th>Version</th><th>Changes</th></tr> 818<tr><td>v11.7.0, v10.16.0</td> 819<td><p>This class was renamed from <code>Zlib</code> to <code>ZlibBase</code>.</p></td></tr> 820<tr><td>v0.5.8</td> 821<td><p><span>Added in: v0.5.8</span></p></td></tr> 822</tbody></table> 823</details> 824</div> 825<p>Not exported by the <code>zlib</code> module. It is documented here because it is the base 826class of the compressor/decompressor classes.</p> 827<p>This class inherits from <a href="stream.html#stream_class_stream_transform"><code>stream.Transform</code></a>, allowing <code>zlib</code> objects to be 828used in pipes and similar stream operations.</p> 829<h4><code>zlib.bytesRead</code><span><a class="mark" href="#zlib_zlib_bytesread" id="zlib_zlib_bytesread">#</a></span></h4> 830<div class="api_metadata"> 831<span>Added in: v8.1.0</span><span>Deprecated since: v10.0.0</span> 832</div> 833<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated: Use <a href="#zlib_zlib_byteswritten"><code>zlib.bytesWritten</code></a> instead.</div><p></p> 834<ul> 835<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 836</ul> 837<p>Deprecated alias for <a href="#zlib_zlib_byteswritten"><code>zlib.bytesWritten</code></a>. This original name was chosen 838because it also made sense to interpret the value as the number of bytes 839read by the engine, but is inconsistent with other streams in Node.js that 840expose values under these names.</p> 841<h4><code>zlib.bytesWritten</code><span><a class="mark" href="#zlib_zlib_byteswritten" id="zlib_zlib_byteswritten">#</a></span></h4> 842<div class="api_metadata"> 843<span>Added in: v10.0.0</span> 844</div> 845<ul> 846<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 847</ul> 848<p>The <code>zlib.bytesWritten</code> property specifies the number of bytes written to 849the engine, before the bytes are processed (compressed or decompressed, 850as appropriate for the derived class).</p> 851<h4><code>zlib.close([callback])</code><span><a class="mark" href="#zlib_zlib_close_callback" id="zlib_zlib_close_callback">#</a></span></h4> 852<div class="api_metadata"> 853<span>Added in: v0.9.4</span> 854</div> 855<ul> 856<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 857</ul> 858<p>Close the underlying handle.</p> 859<h4><code>zlib.flush([kind, ]callback)</code><span><a class="mark" href="#zlib_zlib_flush_kind_callback" id="zlib_zlib_flush_kind_callback">#</a></span></h4> 860<div class="api_metadata"> 861<span>Added in: v0.5.8</span> 862</div> 863<ul> 864<li><code>kind</code> <strong>Default:</strong> <code>zlib.constants.Z_FULL_FLUSH</code> for zlib-based streams, 865<code>zlib.constants.BROTLI_OPERATION_FLUSH</code> for Brotli-based streams.</li> 866<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 867</ul> 868<p>Flush pending data. Don't call this frivolously, premature flushes negatively 869impact the effectiveness of the compression algorithm.</p> 870<p>Calling this only flushes data from the internal <code>zlib</code> state, and does not 871perform flushing of any kind on the streams level. Rather, it behaves like a 872normal call to <code>.write()</code>, i.e. it will be queued up behind other pending 873writes and will only produce output when data is being read from the stream.</p> 874<h4><code>zlib.params(level, strategy, callback)</code><span><a class="mark" href="#zlib_zlib_params_level_strategy_callback" id="zlib_zlib_params_level_strategy_callback">#</a></span></h4> 875<div class="api_metadata"> 876<span>Added in: v0.11.4</span> 877</div> 878<ul> 879<li><code>level</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a></li> 880<li><code>strategy</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a></li> 881<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 882</ul> 883<p>This function is only available for zlib-based streams, i.e. not Brotli.</p> 884<p>Dynamically update the compression level and compression strategy. 885Only applicable to deflate algorithm.</p> 886<h4><code>zlib.reset()</code><span><a class="mark" href="#zlib_zlib_reset" id="zlib_zlib_reset">#</a></span></h4> 887<div class="api_metadata"> 888<span>Added in: v0.7.0</span> 889</div> 890<p>Reset the compressor/decompressor to factory defaults. Only applicable to 891the inflate and deflate algorithms.</p> 892</section><section><h3><code>zlib.constants</code><span><a class="mark" href="#zlib_zlib_constants_1" id="zlib_zlib_constants_1">#</a></span></h3> 893<div class="api_metadata"> 894<span>Added in: v7.0.0</span> 895</div> 896<p>Provides an object enumerating Zlib-related constants.</p> 897</section><section><h3><code>zlib.createBrotliCompress([options])</code><span><a class="mark" href="#zlib_zlib_createbrotlicompress_options" id="zlib_zlib_createbrotlicompress_options">#</a></span></h3> 898<div class="api_metadata"> 899<span>Added in: v11.7.0, v10.16.0</span> 900</div> 901<ul> 902<li><code>options</code> <a href="zlib.html#zlib_class_brotlioptions" class="type"><brotli options></a></li> 903</ul> 904<p>Creates and returns a new <a href="#zlib_class_zlib_brotlicompress"><code>BrotliCompress</code></a> object.</p> 905</section><section><h3><code>zlib.createBrotliDecompress([options])</code><span><a class="mark" href="#zlib_zlib_createbrotlidecompress_options" id="zlib_zlib_createbrotlidecompress_options">#</a></span></h3> 906<div class="api_metadata"> 907<span>Added in: v11.7.0, v10.16.0</span> 908</div> 909<ul> 910<li><code>options</code> <a href="zlib.html#zlib_class_brotlioptions" class="type"><brotli options></a></li> 911</ul> 912<p>Creates and returns a new <a href="#zlib_class_zlib_brotlidecompress"><code>BrotliDecompress</code></a> object.</p> 913</section><section><h3><code>zlib.createDeflate([options])</code><span><a class="mark" href="#zlib_zlib_createdeflate_options" id="zlib_zlib_createdeflate_options">#</a></span></h3> 914<div class="api_metadata"> 915<span>Added in: v0.5.8</span> 916</div> 917<ul> 918<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 919</ul> 920<p>Creates and returns a new <a href="#zlib_class_zlib_deflate"><code>Deflate</code></a> object.</p> 921</section><section><h3><code>zlib.createDeflateRaw([options])</code><span><a class="mark" href="#zlib_zlib_createdeflateraw_options" id="zlib_zlib_createdeflateraw_options">#</a></span></h3> 922<div class="api_metadata"> 923<span>Added in: v0.5.8</span> 924</div> 925<ul> 926<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 927</ul> 928<p>Creates and returns a new <a href="#zlib_class_zlib_deflateraw"><code>DeflateRaw</code></a> object.</p> 929<p>An upgrade of zlib from 1.2.8 to 1.2.11 changed behavior when <code>windowBits</code> 930is set to 8 for raw deflate streams. zlib would automatically set <code>windowBits</code> 931to 9 if was initially set to 8. Newer versions of zlib will throw an exception, 932so Node.js restored the original behavior of upgrading a value of 8 to 9, 933since passing <code>windowBits = 9</code> to zlib actually results in a compressed stream 934that effectively uses an 8-bit window only.</p> 935</section><section><h3><code>zlib.createGunzip([options])</code><span><a class="mark" href="#zlib_zlib_creategunzip_options" id="zlib_zlib_creategunzip_options">#</a></span></h3> 936<div class="api_metadata"> 937<span>Added in: v0.5.8</span> 938</div> 939<ul> 940<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 941</ul> 942<p>Creates and returns a new <a href="#zlib_class_zlib_gunzip"><code>Gunzip</code></a> object.</p> 943</section><section><h3><code>zlib.createGzip([options])</code><span><a class="mark" href="#zlib_zlib_creategzip_options" id="zlib_zlib_creategzip_options">#</a></span></h3> 944<div class="api_metadata"> 945<span>Added in: v0.5.8</span> 946</div> 947<ul> 948<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 949</ul> 950<p>Creates and returns a new <a href="#zlib_class_zlib_gzip"><code>Gzip</code></a> object. 951See <a href="#zlib_zlib">example</a>.</p> 952</section><section><h3><code>zlib.createInflate([options])</code><span><a class="mark" href="#zlib_zlib_createinflate_options" id="zlib_zlib_createinflate_options">#</a></span></h3> 953<div class="api_metadata"> 954<span>Added in: v0.5.8</span> 955</div> 956<ul> 957<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 958</ul> 959<p>Creates and returns a new <a href="#zlib_class_zlib_inflate"><code>Inflate</code></a> object.</p> 960</section><section><h3><code>zlib.createInflateRaw([options])</code><span><a class="mark" href="#zlib_zlib_createinflateraw_options" id="zlib_zlib_createinflateraw_options">#</a></span></h3> 961<div class="api_metadata"> 962<span>Added in: v0.5.8</span> 963</div> 964<ul> 965<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 966</ul> 967<p>Creates and returns a new <a href="#zlib_class_zlib_inflateraw"><code>InflateRaw</code></a> object.</p> 968</section><section><h3><code>zlib.createUnzip([options])</code><span><a class="mark" href="#zlib_zlib_createunzip_options" id="zlib_zlib_createunzip_options">#</a></span></h3> 969<div class="api_metadata"> 970<span>Added in: v0.5.8</span> 971</div> 972<ul> 973<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 974</ul> 975<p>Creates and returns a new <a href="#zlib_class_zlib_unzip"><code>Unzip</code></a> object.</p> 976</section><section><h3>Convenience methods<span><a class="mark" href="#zlib_convenience_methods" id="zlib_convenience_methods">#</a></span></h3> 977 978<p>All of these take a <a href="buffer.html#buffer_class_buffer"><code>Buffer</code></a>, <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray"><code>TypedArray</code></a>, <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView"><code>DataView</code></a>, 979<a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer"><code>ArrayBuffer</code></a> or string as the first argument, an optional second argument 980to supply options to the <code>zlib</code> classes and will call the supplied callback 981with <code>callback(error, result)</code>.</p> 982<p>Every method has a <code>*Sync</code> counterpart, which accept the same arguments, but 983without a callback.</p> 984<h4><code>zlib.brotliCompress(buffer[, options], callback)</code><span><a class="mark" href="#zlib_zlib_brotlicompress_buffer_options_callback" id="zlib_zlib_brotlicompress_buffer_options_callback">#</a></span></h4> 985<div class="api_metadata"> 986<span>Added in: v11.7.0, v10.16.0</span> 987</div> 988<ul> 989<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 990<li><code>options</code> <a href="zlib.html#zlib_class_brotlioptions" class="type"><brotli options></a></li> 991<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 992</ul> 993<h4><code>zlib.brotliCompressSync(buffer[, options])</code><span><a class="mark" href="#zlib_zlib_brotlicompresssync_buffer_options" id="zlib_zlib_brotlicompresssync_buffer_options">#</a></span></h4> 994<div class="api_metadata"> 995<span>Added in: v11.7.0, v10.16.0</span> 996</div> 997<ul> 998<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 999<li><code>options</code> <a href="zlib.html#zlib_class_brotlioptions" class="type"><brotli options></a></li> 1000</ul> 1001<p>Compress a chunk of data with <a href="#zlib_class_zlib_brotlicompress"><code>BrotliCompress</code></a>.</p> 1002<h4><code>zlib.brotliDecompress(buffer[, options], callback)</code><span><a class="mark" href="#zlib_zlib_brotlidecompress_buffer_options_callback" id="zlib_zlib_brotlidecompress_buffer_options_callback">#</a></span></h4> 1003<div class="api_metadata"> 1004<span>Added in: v11.7.0, v10.16.0</span> 1005</div> 1006<ul> 1007<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1008<li><code>options</code> <a href="zlib.html#zlib_class_brotlioptions" class="type"><brotli options></a></li> 1009<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1010</ul> 1011<h4><code>zlib.brotliDecompressSync(buffer[, options])</code><span><a class="mark" href="#zlib_zlib_brotlidecompresssync_buffer_options" id="zlib_zlib_brotlidecompresssync_buffer_options">#</a></span></h4> 1012<div class="api_metadata"> 1013<span>Added in: v11.7.0, v10.16.0</span> 1014</div> 1015<ul> 1016<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1017<li><code>options</code> <a href="zlib.html#zlib_class_brotlioptions" class="type"><brotli options></a></li> 1018</ul> 1019<p>Decompress a chunk of data with <a href="#zlib_class_zlib_brotlidecompress"><code>BrotliDecompress</code></a>.</p> 1020<h4><code>zlib.deflate(buffer[, options], callback)</code><span><a class="mark" href="#zlib_zlib_deflate_buffer_options_callback" id="zlib_zlib_deflate_buffer_options_callback">#</a></span></h4> 1021<div class="api_metadata"> 1022<details class="changelog"><summary>History</summary> 1023<table> 1024<tbody><tr><th>Version</th><th>Changes</th></tr> 1025<tr><td>v9.4.0</td> 1026<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1027<tr><td>v8.0.0</td> 1028<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1029<tr><td>v8.0.0</td> 1030<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1031<tr><td>v0.6.0</td> 1032<td><p><span>Added in: v0.6.0</span></p></td></tr> 1033</tbody></table> 1034</details> 1035</div> 1036<ul> 1037<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1038<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1039<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1040</ul> 1041<h4><code>zlib.deflateSync(buffer[, options])</code><span><a class="mark" href="#zlib_zlib_deflatesync_buffer_options" id="zlib_zlib_deflatesync_buffer_options">#</a></span></h4> 1042<div class="api_metadata"> 1043<details class="changelog"><summary>History</summary> 1044<table> 1045<tbody><tr><th>Version</th><th>Changes</th></tr> 1046<tr><td>v9.4.0</td> 1047<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1048<tr><td>v8.0.0</td> 1049<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1050<tr><td>v8.0.0</td> 1051<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1052<tr><td>v0.11.12</td> 1053<td><p><span>Added in: v0.11.12</span></p></td></tr> 1054</tbody></table> 1055</details> 1056</div> 1057<ul> 1058<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1059<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1060</ul> 1061<p>Compress a chunk of data with <a href="#zlib_class_zlib_deflate"><code>Deflate</code></a>.</p> 1062<h4><code>zlib.deflateRaw(buffer[, options], callback)</code><span><a class="mark" href="#zlib_zlib_deflateraw_buffer_options_callback" id="zlib_zlib_deflateraw_buffer_options_callback">#</a></span></h4> 1063<div class="api_metadata"> 1064<details class="changelog"><summary>History</summary> 1065<table> 1066<tbody><tr><th>Version</th><th>Changes</th></tr> 1067<tr><td>v8.0.0</td> 1068<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1069<tr><td>v8.0.0</td> 1070<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1071<tr><td>v0.6.0</td> 1072<td><p><span>Added in: v0.6.0</span></p></td></tr> 1073</tbody></table> 1074</details> 1075</div> 1076<ul> 1077<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1078<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1079<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1080</ul> 1081<h4><code>zlib.deflateRawSync(buffer[, options])</code><span><a class="mark" href="#zlib_zlib_deflaterawsync_buffer_options" id="zlib_zlib_deflaterawsync_buffer_options">#</a></span></h4> 1082<div class="api_metadata"> 1083<details class="changelog"><summary>History</summary> 1084<table> 1085<tbody><tr><th>Version</th><th>Changes</th></tr> 1086<tr><td>v9.4.0</td> 1087<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1088<tr><td>v8.0.0</td> 1089<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1090<tr><td>v8.0.0</td> 1091<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1092<tr><td>v0.11.12</td> 1093<td><p><span>Added in: v0.11.12</span></p></td></tr> 1094</tbody></table> 1095</details> 1096</div> 1097<ul> 1098<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1099<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1100</ul> 1101<p>Compress a chunk of data with <a href="#zlib_class_zlib_deflateraw"><code>DeflateRaw</code></a>.</p> 1102<h4><code>zlib.gunzip(buffer[, options], callback)</code><span><a class="mark" href="#zlib_zlib_gunzip_buffer_options_callback" id="zlib_zlib_gunzip_buffer_options_callback">#</a></span></h4> 1103<div class="api_metadata"> 1104<details class="changelog"><summary>History</summary> 1105<table> 1106<tbody><tr><th>Version</th><th>Changes</th></tr> 1107<tr><td>v9.4.0</td> 1108<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1109<tr><td>v8.0.0</td> 1110<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1111<tr><td>v8.0.0</td> 1112<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1113<tr><td>v0.6.0</td> 1114<td><p><span>Added in: v0.6.0</span></p></td></tr> 1115</tbody></table> 1116</details> 1117</div> 1118<ul> 1119<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1120<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1121<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1122</ul> 1123<h4><code>zlib.gunzipSync(buffer[, options])</code><span><a class="mark" href="#zlib_zlib_gunzipsync_buffer_options" id="zlib_zlib_gunzipsync_buffer_options">#</a></span></h4> 1124<div class="api_metadata"> 1125<details class="changelog"><summary>History</summary> 1126<table> 1127<tbody><tr><th>Version</th><th>Changes</th></tr> 1128<tr><td>v9.4.0</td> 1129<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1130<tr><td>v8.0.0</td> 1131<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1132<tr><td>v8.0.0</td> 1133<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1134<tr><td>v0.11.12</td> 1135<td><p><span>Added in: v0.11.12</span></p></td></tr> 1136</tbody></table> 1137</details> 1138</div> 1139<ul> 1140<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1141<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1142</ul> 1143<p>Decompress a chunk of data with <a href="#zlib_class_zlib_gunzip"><code>Gunzip</code></a>.</p> 1144<h4><code>zlib.gzip(buffer[, options], callback)</code><span><a class="mark" href="#zlib_zlib_gzip_buffer_options_callback" id="zlib_zlib_gzip_buffer_options_callback">#</a></span></h4> 1145<div class="api_metadata"> 1146<details class="changelog"><summary>History</summary> 1147<table> 1148<tbody><tr><th>Version</th><th>Changes</th></tr> 1149<tr><td>v9.4.0</td> 1150<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1151<tr><td>v8.0.0</td> 1152<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1153<tr><td>v8.0.0</td> 1154<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1155<tr><td>v0.6.0</td> 1156<td><p><span>Added in: v0.6.0</span></p></td></tr> 1157</tbody></table> 1158</details> 1159</div> 1160<ul> 1161<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1162<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1163<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1164</ul> 1165<h4><code>zlib.gzipSync(buffer[, options])</code><span><a class="mark" href="#zlib_zlib_gzipsync_buffer_options" id="zlib_zlib_gzipsync_buffer_options">#</a></span></h4> 1166<div class="api_metadata"> 1167<details class="changelog"><summary>History</summary> 1168<table> 1169<tbody><tr><th>Version</th><th>Changes</th></tr> 1170<tr><td>v9.4.0</td> 1171<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1172<tr><td>v8.0.0</td> 1173<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1174<tr><td>v8.0.0</td> 1175<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1176<tr><td>v0.11.12</td> 1177<td><p><span>Added in: v0.11.12</span></p></td></tr> 1178</tbody></table> 1179</details> 1180</div> 1181<ul> 1182<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1183<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1184</ul> 1185<p>Compress a chunk of data with <a href="#zlib_class_zlib_gzip"><code>Gzip</code></a>.</p> 1186<h4><code>zlib.inflate(buffer[, options], callback)</code><span><a class="mark" href="#zlib_zlib_inflate_buffer_options_callback" id="zlib_zlib_inflate_buffer_options_callback">#</a></span></h4> 1187<div class="api_metadata"> 1188<details class="changelog"><summary>History</summary> 1189<table> 1190<tbody><tr><th>Version</th><th>Changes</th></tr> 1191<tr><td>v9.4.0</td> 1192<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1193<tr><td>v8.0.0</td> 1194<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1195<tr><td>v8.0.0</td> 1196<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1197<tr><td>v0.6.0</td> 1198<td><p><span>Added in: v0.6.0</span></p></td></tr> 1199</tbody></table> 1200</details> 1201</div> 1202<ul> 1203<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1204<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1205<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1206</ul> 1207<h4><code>zlib.inflateSync(buffer[, options])</code><span><a class="mark" href="#zlib_zlib_inflatesync_buffer_options" id="zlib_zlib_inflatesync_buffer_options">#</a></span></h4> 1208<div class="api_metadata"> 1209<details class="changelog"><summary>History</summary> 1210<table> 1211<tbody><tr><th>Version</th><th>Changes</th></tr> 1212<tr><td>v9.4.0</td> 1213<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1214<tr><td>v8.0.0</td> 1215<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1216<tr><td>v8.0.0</td> 1217<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1218<tr><td>v0.11.12</td> 1219<td><p><span>Added in: v0.11.12</span></p></td></tr> 1220</tbody></table> 1221</details> 1222</div> 1223<ul> 1224<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1225<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1226</ul> 1227<p>Decompress a chunk of data with <a href="#zlib_class_zlib_inflate"><code>Inflate</code></a>.</p> 1228<h4><code>zlib.inflateRaw(buffer[, options], callback)</code><span><a class="mark" href="#zlib_zlib_inflateraw_buffer_options_callback" id="zlib_zlib_inflateraw_buffer_options_callback">#</a></span></h4> 1229<div class="api_metadata"> 1230<details class="changelog"><summary>History</summary> 1231<table> 1232<tbody><tr><th>Version</th><th>Changes</th></tr> 1233<tr><td>v9.4.0</td> 1234<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1235<tr><td>v8.0.0</td> 1236<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1237<tr><td>v8.0.0</td> 1238<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1239<tr><td>v0.6.0</td> 1240<td><p><span>Added in: v0.6.0</span></p></td></tr> 1241</tbody></table> 1242</details> 1243</div> 1244<ul> 1245<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1246<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1247<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1248</ul> 1249<h4><code>zlib.inflateRawSync(buffer[, options])</code><span><a class="mark" href="#zlib_zlib_inflaterawsync_buffer_options" id="zlib_zlib_inflaterawsync_buffer_options">#</a></span></h4> 1250<div class="api_metadata"> 1251<details class="changelog"><summary>History</summary> 1252<table> 1253<tbody><tr><th>Version</th><th>Changes</th></tr> 1254<tr><td>v9.4.0</td> 1255<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1256<tr><td>v8.0.0</td> 1257<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1258<tr><td>v8.0.0</td> 1259<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1260<tr><td>v0.11.12</td> 1261<td><p><span>Added in: v0.11.12</span></p></td></tr> 1262</tbody></table> 1263</details> 1264</div> 1265<ul> 1266<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1267<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1268</ul> 1269<p>Decompress a chunk of data with <a href="#zlib_class_zlib_inflateraw"><code>InflateRaw</code></a>.</p> 1270<h4><code>zlib.unzip(buffer[, options], callback)</code><span><a class="mark" href="#zlib_zlib_unzip_buffer_options_callback" id="zlib_zlib_unzip_buffer_options_callback">#</a></span></h4> 1271<div class="api_metadata"> 1272<details class="changelog"><summary>History</summary> 1273<table> 1274<tbody><tr><th>Version</th><th>Changes</th></tr> 1275<tr><td>v9.4.0</td> 1276<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1277<tr><td>v8.0.0</td> 1278<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1279<tr><td>v8.0.0</td> 1280<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1281<tr><td>v0.6.0</td> 1282<td><p><span>Added in: v0.6.0</span></p></td></tr> 1283</tbody></table> 1284</details> 1285</div> 1286<ul> 1287<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1288<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1289<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1290</ul> 1291<h4><code>zlib.unzipSync(buffer[, options])</code><span><a class="mark" href="#zlib_zlib_unzipsync_buffer_options" id="zlib_zlib_unzipsync_buffer_options">#</a></span></h4> 1292<div class="api_metadata"> 1293<details class="changelog"><summary>History</summary> 1294<table> 1295<tbody><tr><th>Version</th><th>Changes</th></tr> 1296<tr><td>v9.4.0</td> 1297<td><p>The <code>buffer</code> parameter can be an <code>ArrayBuffer</code>.</p></td></tr> 1298<tr><td>v8.0.0</td> 1299<td><p>The <code>buffer</code> parameter can be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 1300<tr><td>v8.0.0</td> 1301<td><p>The <code>buffer</code> parameter can be an <code>Uint8Array</code> now.</p></td></tr> 1302<tr><td>v0.11.12</td> 1303<td><p><span>Added in: v0.11.12</span></p></td></tr> 1304</tbody></table> 1305</details> 1306</div> 1307<ul> 1308<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer" class="type"><ArrayBuffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1309<li><code>options</code> <a href="zlib.html#zlib_class_options" class="type"><zlib options></a></li> 1310</ul> 1311<p>Decompress a chunk of data with <a href="#zlib_class_zlib_unzip"><code>Unzip</code></a>.</p></section> 1312 <!-- API END --> 1313 </div> 1314 </div> 1315 </div> 1316 <script> 1317 'use strict'; 1318 { 1319 const kCustomPreference = 'customDarkTheme'; 1320 const userSettings = sessionStorage.getItem(kCustomPreference); 1321 const themeToggleButton = document.getElementById('theme-toggle-btn'); 1322 if (userSettings === null && window.matchMedia) { 1323 const mq = window.matchMedia('(prefers-color-scheme: dark)'); 1324 if ('onchange' in mq) { 1325 function mqChangeListener(e) { 1326 document.body.classList.toggle('dark-mode', e.matches); 1327 } 1328 mq.addEventListener('change', mqChangeListener); 1329 if (themeToggleButton) { 1330 themeToggleButton.addEventListener('click', function() { 1331 mq.removeEventListener('change', mqChangeListener); 1332 }, { once: true }); 1333 } 1334 } 1335 if (mq.matches) { 1336 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